Field of Art
The present disclosure relates to a system and method for adjusting the focus in an ophthalmoscope.
Description of the Related Art
In recent years, scanning light ophthalmoscopes (SLOs) that irradiate the fundus with laser light in two dimensions and receive reflected light therefrom and imaging apparatuses that utilize the interference of low coherence light have been developed as ophthalmic image pickup apparatuses. Thus, SLOs have become important tools for the study of the human retina in both normal and diseased eyes.
The resolution of such ophthalmic image pickup apparatuses has been improved by, for example, achieving high NA of irradiation laser light. However, when an image of the fundus is to be acquired, the image must be acquired through optical tissues including the cornea and the crystalline lens. As the resolution increases, the aberrations of the cornea and the crystalline lens have come to significantly affect the quality of acquired images.
One solution to this issue is an adaptive optics SLO (AO-SLO) in which the adaptive optics (AO) includes a correction optical system that measures the aberration of the eye and corrects the aberration. The AO-SLO or an adaptive optics optical coherence tomograph (AO-OCT) can measure the wavefront of the eye using a Shack-Hartmann wavefront sensor system. A deformable mirror or a spatial-phase modulator can then be driven to correct the measured wavefront, and an image of the fundus is acquired can then be acquired. This technique allows for the AO-SLO or the AO-OCT to obtain high resolution images of fundus despite the aberration introduced by intervening material such as the cornea and the lens of the eye.